@nemobis at least for us, now, at current scale, for the bsky app, "reads" are more expensive (in kilowatts and silicon) than "writes". I don't think this would be particularly more efficient if network distributed the load more to many smaller nodes (vs having big API servers).
it is possible to "shard" parts of network for things like search queries. https://yacy.net/ might be relevant. I don't think that helps with efficiency though?